<?php

if (!defined('BASEPATH'))
    exit('No direct script access allowed');
/**
 * CodeIgniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 1.0
 * @filesource
 */
// ------------------------------------------------------------------------

/**
 * CodeIgniter Hooks Class
 *
 * Provides a mechanism to extend the base system without hacking.
 *
 * @package		CodeIgniter
 * @subpackage	Libraries
 * @category	Libraries
 * @author		ExpressionEngine Dev Team
 * @link		http://codeigniter.com/user_guide/libraries/encryption.html
 */
class CI_Hooks {

    /**
     * Determines wether hooks are enabled
     *
     * @var bool
     */
    var $enabled = FALSE;

    /**
     * List of all hooks set in config/hooks.php
     *
     * @var array
     */
    var $hooks = array();

    /**
     * Determines wether hook is in progress, used to prevent infinte loops
     *
     * @var bool
     */
    var $in_progress = FALSE;

    /**
     * Constructor
     *
     */
    function __construct() {
        $this->_initialize();
        log_message('debug', "Hooks Class Initialized");
    }

    // --------------------------------------------------------------------

    /**
     * Initialize the Hooks Preferences
     *
     * @access	private
     * @return	void
     */
    function _initialize() {
        $CFG = & load_class('Config', 'core');

        // If hooks are not enabled in the config file
        // there is nothing else to do
        if ($CFG->item('enable_hooks') == FALSE) {
            return;
        }

        // Grab the "hooks" definition file.
        // If there are no hooks, we're done.
        if (defined('ENVIRONMENT') AND is_file(APPPATH . 'config/' . ENVIRONMENT . '/hooks.php')) {
            include(APPPATH . 'config/' . ENVIRONMENT . '/hooks.php');
        } elseif (is_file(APPPATH . 'config/hooks.php')) {
            include(APPPATH . 'config/hooks.php');
        }


        if (!isset($hook) OR !is_array($hook)) {
            return;
        }

        $this->hooks = & $hook;
        $this->enabled = TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * Call Hook
     *
     * Calls a particular hook
     *
     * @access	private
     * @param	string	the hook name
     * @return	mixed
     */
    function _call_hook($which = '') {
        if (!$this->enabled OR !isset($this->hooks[$which])) {
            return FALSE;
        }

        if (isset($this->hooks[$which][0]) AND is_array($this->hooks[$which][0])) {
            foreach ($this->hooks[$which] as $val) {
                $this->_run_hook($val);
            }
        } else {
            $this->_run_hook($this->hooks[$which]);
        }

        return TRUE;
    }

    // --------------------------------------------------------------------

    /**
     * Run Hook
     *
     * Runs a particular hook
     *
     * @access	private
     * @param	array	the hook details
     * @return	bool
     */
    function _run_hook($data) {
        if (!is_array($data)) {
            return FALSE;
        }

        // -----------------------------------
        // Safety - Prevents run-away loops
        // -----------------------------------
        // If the script being called happens to have the same
        // hook call within it a loop can happen

        if ($this->in_progress == TRUE) {
            return;
        }

        // -----------------------------------
        // Set file path
        // -----------------------------------

        if (!isset($data['filepath']) OR !isset($data['filename'])) {
            return FALSE;
        }

        $filepath = APPPATH . $data['filepath'] . '/' . $data['filename'];

        if (!file_exists($filepath)) {
            return FALSE;
        }

        // -----------------------------------
        // Set class/function name
        // -----------------------------------

        $class = FALSE;
        $function = FALSE;
        $params = '';

        if (isset($data['class']) AND $data['class'] != '') {
            $class = $data['class'];
        }

        if (isset($data['function'])) {
            $function = $data['function'];
        }

        if (isset($data['params'])) {
            $params = $data['params'];
        }

        if ($class === FALSE AND $function === FALSE) {
            return FALSE;
        }

        // -----------------------------------
        // Set the in_progress flag
        // -----------------------------------

        $this->in_progress = TRUE;

        // -----------------------------------
        // Call the requested class and/or function
        // -----------------------------------

        if ($class !== FALSE) {
            if (!class_exists($class)) {
                require($filepath);
            }

            $HOOK = new $class;
            $HOOK->$function($params);
        } else {
            if (!function_exists($function)) {
                require($filepath);
            }

            $function($params);
        }

        $this->in_progress = FALSE;
        return TRUE;
    }

}

// END CI_Hooks class

/* End of file Hooks.php */
/* Location: ./system/core/Hooks.php */